Dental articulator



April 29, 1941. H, ZIMMERMAN l2,239,835

DENTAL ARTICULATOR Filed Nov. l8, 1957 Patented Apr. 29, 1941 UNITED STATES PATENT korties azsass DENTAL ARTICULATOR Henry Zimmerman, Chicago, Ill.

Application November 8, 1937,'Serial No. 173,337

4 Claims.

This invention relates to dental articulators, used in connection with the mechanical branch of dentistry, where it is desirous to mount, for the purposes of study, adjustment, experiment or observation models or plaster casts of human jaws, teeth, waxbites, dentures or plates, permitting close scrutiny and observation of the occluding and masticating functions, at the same time reproducing the natural movements of the teeth, thereby assuring correct fit fand function in the mouth of such denture plates or other dental accessories.

Another object of the invention resides in the use of a spring structure which provides an ideally universal action enabling theteeth to provide a mutually controllable grinding path thereby guaranteeing a closer and more accurate fitting relationship in the mouth.

Another object of the invention resides in the provision of a novel method for nullifying or arresting the universal exure of the spring members by screws.

Another object of the invention resides in thev provision of simple articulate means permitting of the separation of the upper and lower plate members of the articulator, when it is necessary for the convenience of working upon the plates or dentures, without disturbing the original setting or relationship of the upper and lower dentures.

Another object of the invention is the provision of simple screw locking means for adjustment of the bite relationship.

A still further object of the invention resides in a novel construction, of simple design, durable and economical to manufacture.

Other objects will appear in the following description, of a preferred structure of my invention.

In the drawing illustrating my invention:

Fig. 1 is a top plan view of my invention indicating in dotted lines the lateral movement of the top plate.

Fig. 2 is a cross sectional view on the line 2 2 of Fig. 1.

Fig. 3 is a side elevational view of the device illustrated in Fig. l a portion thereof being shown in section.

Fig. 4 is a fragmentary front view of the strueture shown in Fig. l demonstrating the universal Iaction of the springs.

Fig. 5 is a detail view of the articulating screw member 9.

Fig. 6 is a detail view of the binding screw I9.

Before describing the structure, and use of my device, I would like to point out particularly that,

as far as I know, dental articulators in the past have confined their structure `to the principle whereby a path in the articulator was the main controlling factor in the grinding or the final fitting operation.

This type of articulator would require constant adjustment and manipulation, which made the task tedious and not as ideally correct as desirable. In my particular structure, I have arranged the articulator members so as to offer an absolutely yieldable means, permitting the dentures to follow in a path dened by their own mutual relationship, thruout, similar to the mastcating or chewing operation, and above all to do so unlrampered by any denite path or curve set up on the articulator. This feature I will bring out more fully in the following description.

In Fig. 1 A represents the top plate of the articulator whichV is formed preferably of one piece of sheet metal or other suitable material having a designed contourapproximately as indicated and having two side lugs 5 at right angles to the body with two holes 6 perforated `or drilled therein, and which provide a hingeable support for plate A. i

The openings 1 are intended toprovide a means for allowing the plaster to lodge therein so that `secure anchorage against displacement of jaw model 8 can be effected. The semicircular opening 9 has no other function except to provide clearance when plate A is swung on the hinge members or screws9. The screws 9 are knurled enabling the operator to make adjustment witho-ut the use of any tools, and are provided with a smooth portion IE! and 'a threaded portion II. A hemispherical button I2 with a reduced cylindrical section I3 is riveted to Ithe plate A and bears on the adjusting screw I4 whenever it is desirable to set the articulator for bite adjustment.

The adjusting screw I4 has preferably a large round knurled head I5 and a threaded portion of suitable length which screws into the threaded hole of block I5', Fig. 3 and is shaped as shown.

The block I5 hasa reduced section in its body for purposes of lightness and design. The holes 2l are drilled to receive portions 2l of screw member I8.

The four pointed star lock-nut I6 is provided to permit setting the bite adjustment in a deflnite and Xe-d position. It will be noted that this arrangement is not utilized when grinding in teeth in which case the screw I4 is lowered and locked, out of contact with button I2 permitting mutual contact between the dentures as will hereinafter be explained.

The block I5' is secured by screws I7 to the base B of the articulator, and this block it will be noted also has two threaded holes 2l toreceive the screws I8 which have a knurled knob I9 substantially as shown, a reduced threaded portion 2l) Kand a smooth portion ZI slightly smaller than the threaded portion 2l).

The screws I8 provide a means for rigidly connecting the parts C to block I5', and nullifying the action of the springs 22 which provide the universal action when the screws I8 are removed. This soi-called universal fleXure is best shown in Fig. 4.

The lower plate B is a flat plate used for mounting, thereupon the springs 22 and block I5', and is similar in contour to plate A at its front end being also provided with openingsl similar to 'I, tho not indicated on the drawing for relatively the same purpose, namely the provision of suitable anchorage for the plaster cast 8.

Now I call special attention to the most important elements of my invention. They are the springs 22 land it should be noted that they are close wound springs and fastened to the base by studs 23 having an enlarged threaded portion 24 to suit the inner thread like form of springs 22 a similar projection 25 being a part of bearing studs C b-y virtue of which the studs C are similarly fastened to springs 22.

I-Iere I should like to call attention to the space between thepartsV 24 and 25 which is virtually the free portion of the spring and which is disposed toprovide the ideally universal action I find so highly desirable in this work.

To describe further the member C it will be noted that there is an enlarged portion 25 having a slot 28 adapted to receive the lug 5 of plate A and also having the inner shoulders 21 cut under as at 28 to provide ample clearance when the articulator is swung on its lug-like hinges 5. These inner shoulders 2'I are threaded at II', to receive thread portion II of screw member 9. The studs 21 are provided with threaded holes 2li', to receive the portion 20 of screw I8 and drilled holes Ill', for smooth portion I0 of screw member 9.

The plates or dentures referred to in the description are shown and designated by D and E. In use when it is desired to set up models of jaws in the articulator, it is done as follows. First one jaw model is set up, on the lower plate, and this can be done with screws 9 removed. 'I'hen the screws 9 may be replaced, it being understood that the screws I8 are also in place, the upper jaw model is then inthe proper relationship to the lower jaw model as indicated by wax bite or other common method known in dental practice. Therbite can then be set by virtue of screw Ill and lock-nut IS as heretofore mentioned and the setting thus obtained used for forming the restoration frame work and for setting the teeth to approximate alignment.

From this point on the dentures are made and processed in the usual manner, until the stage is reached where the dentures t almost perfectly, having been ground to relieve high spots.

After the operator is satisfied withv the close fitting of the dentures, and all interfering cusps having been ground off, a paste of suitable abrasive is prepared and spread on the dentures and the final finishing or lapping operation performed.

Y. The screws I8 in this instance are removed from their threaded sockets 20 and the springs are now in a universally yieldable position allowing the dentures themselves to act as the controlling or governing factors assuring a mutually fitted set of dentures. Primarily, this is the result of my following out and duplicating the natural processes of mastication, and, moreover, because of the structure I have provided that irnparts this naturalaction to my articulator.

The grinding is done by the operator when the dentures are set up as shown in Fig. 2, the operator holding the instrument in both hands so that plate member A is grasped in one hand, and plate member B is held in the other, the two hands working universally the dentures grinding the way by their own peculiar configuration. I might also mention that with my articulator it is not necessary to mount teeth in dentures too accurately, in fact even tho kthe teeth on one side of a denture be longer, than those on the opposing side of the same denture, and, of course, the complementary teeth in the opposite denture being set to compensate for this irregularity, yet with my articulator, a perfect fitting denture will be the result and, while such a fit may not be as nice in appearance, yet most important of all it will provide the wearer with a comfortable set of plates. I merely mention this exaggerated condition to show how my device will simplify the making of properly fitting dentures.

My invention will thus permit laterally protrusive as well as retrusive grinding actions simulating the natural actions of the teeth during mastication and occlusion.

While I have thus described my invention, I do not wish to be limited to the drawing which represents a preferred embodiment, it being understood, nevertheless, that my invention may be otherwise constructed, providing the structure is within the scope of the appended claims.

I claim:

1. A dental articulator comprising a base member, a pairl of spaced-apart longitudinal laterally iieXible spring members extending upwardly from said base member and anchored thereto at their lower ends, -a pair of connector posts disposed respectively upon the upper ends of said spring members, a denture supporting plate above and in registry with said base member, means pivotally connecting said plate at an edge to said posts for pivotal movement about a horizontal axis, a stud member on said base and having a section disposed between said posts, means adjustably mounted on said stud member section to gauge and limit downward pivotal movement of said denture supporting plate, and locking means Afor securing said connector posts in a selected position relatively to said base member, said locking means being cooperable with said stud member and also being renderable ineffective to enable movement of said posts and the denture supporting plate relatively to said base incident to flexing said spring members.

2. A dental articulator comprising a base member, a denture supporting plate above and in registry with said base member, a pair of spacedapart connector posts in pivotal support of said plate at an edge thereof, a stud member on said base member and having a section disposed between said posts, a pair of spring members on said base and respectively in support of said connector posts, said spring members being laterally flexible to adapt movement of the plate laterally for imparting a grinding movement to a denture thereon, Vand threaded members respectively on said posts, said threaded members being removably engageable with said stud member for precluding such movement of the plate and for predeterminedly stationing said posts with respect to said base member.

3. In a dental articulator, a denture holding base member, a lug member on said base member, a denture holding plate, and a pair of standards in pivotal support of said plate, said standards each comprising an upright helical spring anchored at its lower end to the base member and a transversely apertured connector post on the upper end of said spring, said standards being thus anchored at opposite sides of said lug member, means pivotally connecting said denture holding plate with said posts, and threaded means disposed in the apertures of said posts and removably engageable with said lug member for retaining the connector posts in a desired xed relation with the base member.

4. In a dental articulator, a denture holding base member, a denture holding plate, and a pair of standards in pivotal support of said plate, said standards each comprising an upright helical spring and a connector post having a threaded section corresponding in pitch With the helical turns in such spring and being in threaded relation with the upper end thereof, a pair of anchor members secured to the base member and each having a threaded section corresponding in pitch with the helical turns of said springs and being respectively inv threaded relation with the lower ends thereof for holding said springs in anchored relation with the base member, and means pivotally connecting said holding plate onto said connecting members.

HENRY ZIMMERMAN. 

